Irish Names: Ó, Ní, Mac and What They Mean
How Irish surnames work, the meaning of Ó, Mac and Ní, common first names in Irish, and how to say English surnames in Irish.
Irish names are full of history. Understanding the small words in them helps you read and pronounce them.
The small words
| Word | Meaning | Example |
|---|---|---|
| Ó | descendant of | Ó Briain (O'Brien) |
| Mac | son of | Mac Carthaigh (McCarthy) |
| Ní | daughter of (a woman with an Ó name) | Aoife Ní Bhriain |
| Nic | daughter of (a woman with a Mac name) | Máire Nic Carthaigh |
Because Irish surnames carry the male ancestor's name, a woman's surname changes form: Ó Briain becomes Ní Bhriain. Note the lenition after Ní.
Some surnames in Irish
| English | Irish |
|---|---|
| O'Brien | Ó Briain |
| Murphy | Ó Murchú |
| Kelly | Ó Ceallaigh |
| Sullivan | Ó Súilleabháin |
| McCarthy | Mac Carthaigh |
First names in Irish
| English | Irish |
|---|---|
| John | Seán |
| Mary | Máire |
| Patrick | Pádraig |
| Kevin | Caoimhín |
| Kathleen | Caitlín |
Irish first names use fadas and mutations that don't appear in English:
- Seán (SHAWN), Pádraig (PAW-drig), Oisín (uh-SHEEN)
- Niamh (NEEV), Aoife (EE-fa), Siobhán (shiv-AWN)
Names in speech
When addressing someone, Irish lenites the name: A Sheáin (Seán!), A Mháire (Máire!), A Phádraig (Pádraig!).
Tips
- Learn how to say your own name in Irish.
- Learn Ó, Mac, Ní and Nic as a set.
- Use the dictionary to check forms and spellings.
English Irish Dictionary
Offline English–Irish (Gaeilge) dictionary with clear, accurate meanings
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